Motor vehicle body equipped with retaining means for limiting door intrusion inside the passenger compartment upon lateral impact

ABSTRACT

The invention concerns door retaining means comprising at least a retention pin fixed to the side-member provided in the door lining opposite the pin when the door is closed.

The present invention concerns a motor vehicle body equipped withretaining means for limiting intrusion of a door inside the passengercompartment upon a lateral impact to which the vehicle is subjected.

So-called passive security in the area of motor vehicles is the focus ofmultiple developments. In particular, the protection of the occupants ofthe vehicles during a lateral impact is one of the major technicalpreoccupations. To this effect, it is necessary to limit as much aspossible the deformation of the door or doors which are directly incontact with the living being or the object upon the impact, and thus,its intrusion inside the passenger compartment of the vehicle concerned.The own rigidity of each of the doors concerned, its lateral resistanceensured by the lock, the strike, the hinges, the front and middlepillars of the vehicle as well as the extension of the door to cover theside beam and of the side beam with the external portion in contactduring the impact contribute strongly to limit intrusion of the door.

However, classical design and manufacturing rules are out of date, onthe one hand, for certain configurations of the vehicle, such as, forexample, when the seating of the vehicle must be low or when the doorsmust have a high length, and on the other hand, when the protection ofthe occupants must be absolutely ensured. In those cases, it becomesnecessary to modify the manufacture of the opening systems and of theirassociated door by adding means for retaining the door to limit itsintrusion inside the passenger compartment.

Several types of retaining means have already been proposed.

U.S. Pat. No. 5,806,917 discloses a system for retaining a front doorconstituted by keys having a trapezoidal shape, which are disposed onthe door lining and which come to be inserted in recesses having aconjugated shape, which are disposed on the vehicle body around the doorframe. This system provides various anchor points in the periphery ofthe opening element but does not set forth any anchor point on thebottom line of the door. The lower resistance of the door is obtainedvia a beam which comes to bear on the lateral portions of the door entryand which, as a result, works by flexion and extension combined. Toensure the effectiveness of this beam, it is necessary to use hardalloys which are expensive, or to give a high mass to the beam, which isdetrimental to the operational ability of the door. Besides, theimplantation of the recesses implies that style concessions for the doorentry must be made, and, as a consequence, additional constraints on thecontrol of water tightness of the hollow bodies.

Another type of retaining means consists in delimiting the lower portionof the door in the shape of an L whose horizontal branch comes to lodgeitself in a groove provided in the side of the passenger compartment.The L thus provided is covered by an ornamental cover made of rubberwhich comes in contact with another ornamental cover fixed on thevehicle body, which forms a supple cover, thus obstructing the grooveprovided on the side of the passenger compartment. To maintain acontinuity of style on the side of the passenger compartment below thedoor, an ornamental cover made of plastic material and having a coloridentical to that of the vehicle body is fixed thereto. Upon lateralimpact, the L comes to bear in the groove and, as a result, it works byflexion. The door, thus pinched between the living being and/or theobject in contact with the vehicle, is then maintained at its lowerportion in order to prevent the lower line of the door from giving way.The effectiveness of this retaining means depends strongly on theresistance of the L inside the associated groove on the side of thepassenger compartment, which can be improved only by the pinching effecton the door lining on the side of the passenger compartment. Theinvestments and the cost of this solution are high. Indeed, the numberof parts used is high, some of them having a high price per item, suchas the lower body ornamental cover in plastic material having a coloridentical to that of the body. In addition, the cost of the associatedlogistics is high, and the assembly time is long. Another drawback ofthis solution is that the support of the two lower seals results in ahigh risk of noise when the vehicle is moving. Finally, the style isdegraded, on the one hand, by the presence of a lower cutting line ofthe door which is necessarily straight and angular, and on the otherhand, by the presence of a groove closing seal on the side of thepassenger compartment which is large and has a dark appearance.

A third type of retaining means consists in rigid lugs which protrudefrom the door lining at its lower portion and which are fixed in ahollow body via a stiffener. These rigid lugs come to be lodged inrecesses provided on the side of the passenger compartment and definedby rubber parts which also serve to ensure water tightness. From anoperational point of view, this solution is close to the solutionpreviously described and its efficacy depends on the resistance of thelug in the associated hole on the side of the passenger compartment. Thecombination lugs-stiffener works by flexion-torsion and its resistanceis improved only by the pinching effect between the passengercompartment side and the living being and/or the object in contactduring the impact. The required dimensioning of the stiffener and of thelugs results in a degradation of the mass of the opening element. Theinvestments for this solution are not negligible and are systematic forthe stiffener since its re-application as is is not possible in the caseof doors having different lengths. The number of parts is also high,which also increases the cost of this solution. The implantation of thelug recess seals also requires making style concessions regarding thedoor entry, and improving water tightness of the associated hollowbodies.

The objective of the invention is then to eliminate all or part of thedrawbacks of the above-mentioned retaining means and to propose meansfor retaining a motor vehicle door upon a lateral impact to which thevehicle is subjected which are effective, low-cost, and whoseimplantation does not degrade the style of the vehicle.

To this effect, an object of the invention is a motor vehicle bodycomprising at least one door opening, a portion of which comprises atleast one side beam covered by a skin constituting the passengercompartment side, a door rotatably mounted around the opening to closeor open this opening and whose lining comes in contact at leastpartially with the skin in a closed position of the door, and means forretaining the door to limit its intrusion inside the passengercompartment upon a lateral impact to which the vehicle is subjected,characterized in that the means for retaining the door comprise at leastone retention pin fixed to the side beam and a hole provided in the doorlining facing the retention pin when the door is in the closed position.

Advantageously, the retention pin is fixed, in particular by welding orscrewing, to the web of the side beam.

Advantageously also, the hole is a hole bound on the door lining.

According to a preferred embodiment of the invention, the means forretaining the door comprise two retention pins and two holes eachrespectively facing a retention pin when the door is in the closedposition and distributed in the vicinity of the center of entry of thedoor.

According to a variant of the invention, the retention pin(s) is (are)fixed to a ( ) counter element(s) stamped locally on the side beam(s).

According to another variant of the invention, the retention pin(s) is(are) fixed on a continuous groove provided over the whole length of theweb of the side beam.

Advantageously also, the thickness of the portion of the skin facing theretention pin is reduced so as to facilitate the perforation thereofupon the lateral impact to which the vehicle is subjected.

Advantageously also, the door comprises at least one cross-memberimplanted between the lining and the door panel and disposed at thebottom of the hole to avoid the tearing off thereof upon the lateralimpact by the retention pin.

Preferably, this cross-member has an internal profile complementary tothat of the retention pin.

Other advantageous details and characteristics will appear upon readingthe detailed description of an examplary embodiment of the invention inreference to the following figures wherein:

FIG. 1 is a transversal cross-section view of a front portion of avehicle body according to the invention before the lateral impact withan impact fence;

FIG. 2 is a cross-section view of a front portion of a vehicle bodyaccording to the invention after the lateral impact with the impactfence;

FIG. 3 is an enlarged view of a front door entry according to FIGS. 1and 2.

FIG. 4 is an enlarged view of a front door entry with a continuousgroove;

FIG. 5 is an enlarged view of a pin and hole area of FIG. 1.

FIG. 1 shows a transversal cross-section view of a front portion 1 of amotor vehicle body according to the invention, in the area of the frontdoor entry.

This front portion 1 of the vehicle body comprises, in a manner known initself, a door opening 2 whose lower portion is a side beam 21.

A retention pin 210 is welded on the external face 21 a of the web ofthe side beam 21.

A skin 22 constituting the side of the passenger compartment of thevehicle is welded on the outside of the side beam 21. The internal face22 a of this skin 22 has a marking in the shape of a cross 221 facingthe retention pin 210.

This front portion 1 of the vehicle body has also a front door 3 mountedvertically rotatably around the door opening 2 by means of hinges, whichare known and not shown here.

This front door 3 has a door lining 31 and an external panel 32 fixed tothis lining 31 in a manner known in itself. Inside this door 3 is placeda cross-member 33 facing an open bound hole 34 provided in the doorlining 31. This cross-member 33 has an internal profile complementary tothat of the retention pin 210.

Water tightness between the lower portion of the door entry and thefront door 3 is ensured by two seals 4, 5 fixed to the web of the sidebeam 21 and to the door lining 5, respectively.

FIG. 2 shows a view of the front potion which has just been describedimmediately after it has been subjected to an impact with an impactfence 6 corresponding to the impact norms in force.

On this Figure, it is observed that the external panel 32 of the frontdoor 3 is bent out of shape and that the retention pin 210 is lodged inthe cross-member 33. The latter makes it possible to prevent theretention pin 210 from appearing on the outside of the vehicle after theimpact, i.e., to avoid parts aggressive to a living being.

Upon the lateral impact, the fence 6 comes to compress, in a firstperiod, the door lining 31 and the skin 22 constituting the side of thepassenger compartment onto the retention pin 210. The thickness of theside of the passenger compartment being smaller than the web of the sidebeam 21 and than the door lining 31, the retention pin 210 piercesthrough the side of the passenger compartment to become lodged in thebound hole 34 of the door lining 31.

The front door 3 is thus so-to-say hooked onto the vehicle base and itssliding movement above the side beam 21 is stopped. The intrusion of thefront door 3 inside the passenger compartment is thus limited.

FIG. 3 is an enlarged view of the door entry according to the inventionon which it is observed that the retention pin 210 is fixed on a locallystamped counter element 211 of the web of the side beam. Thisimplantation is linked to the proximity of the external face 21 a of theweb of the side beam with the styling volume formed by the skin 22 aconstituting the side of the passenger compartment. This locally stampedcounter element does absolutely not disturb the energetic absorption ofthe side beam in the case of a frontal impact to which the vehicle issubjected.

FIG. 4 corresponds to FIG. 3 except that the retentions pins aredisposed in a continuous groove 213 of the side beam.

The invention just described has several advantages with respect toexisting retaining means:

-   -   the lower portion of the door is maintained via a rigid embedded        system. The lower restraint of the door does not depend on        deformations of the door which works by extension and not by        flexion or torsion;    -   the retaining means are not visible from the outside of the        vehicle and do not result in a degradation of style;    -   the cost in terms of investments and cost price is very low;    -   the mass of the door is not increased;    -   the water tightness arrangement does not need to be modified.

Of course, it is self-evident that improvements can be made withoutgoing beyond the scope of the invention.

Thus, the number of retention pins and associated holes can be adaptedas a function of the length of the door and of the levels of the forcerequired to retain it.

Similarly, in the hypothesis where the perforation of the skin is notdone sufficiently early upon the lateral impact, a weakening thereof canbe provided, such as the marking in the shape of a cross mentionedabove, which, by reducing locally the thickness of the metal sheet,facilitates the perforation. Other solutions to reduce locally thethickness of the metal sheet can be envisioned. For example, acounter-stamping in the shape of a circle having a small diameter and asmall depth with a reduced stamping radius can be envisioned.

In addition, the dimension and the relative position of the bound holeon the door lining with respect to the retention pin can be modified.

Finally, if the forces observed during a lateral impact risk tearing offthe skin, the number of retention pins can be increased to distributethe forces and the return of the hole edge can be replaced by asling-type washer.

1. Motor vehicle body comprising at least one door opening, a portion ofwhich comprises at least one side beam covered by a skin constitutingthe side of the passenger compartment, a door rotatably mounted aroundthe opening to close or open this opening and means for retaining thedoor to limit its intrusion inside the passenger compartment upon alateral impact to which the vehicle is subjected, wherein the means forretaining the door comprise at least one fixed retention pin attached tothe side beam so as to be covered by the skin and a hole provided in thedoor lining facing the retention pin when the door is in the closedposition such that the pin pierces through the skin to be lodged in thehole of the door lining upon lateral impact.
 2. Motor vehicle bodyaccording to claim 1, wherein the retention pin is fixed to a web of theside beam.
 3. Motor vehicle body according to claim 1, wherein the holeis a delimited hole on the door lining.
 4. Motor vehicle body accordingto claim 1, wherein the means for retaining the door comprise tworetention pins and two holes each respectively facing a retention pinwhen the door is in the closed position and distributed in the vicinityof the center of entry of the door.
 5. Motor vehicle body according toclaim 1, wherein each of the at least one retention pin is fixed to acounter element stamped locally on the side beam.
 6. Motor vehicle bodyaccording to claim 1, wherein each of the at least one retention pin isfixed on a continuous groove provided over the whole length of a web ofthe side beam.
 7. Motor vehicle body according to claim 1, wherein thethickness of the portion of the skin facing the retention pin is reducedin order to facilitate the perforation thereof upon the lateral impactto which the vehicle is subjected.
 8. Motor vehicle body according toclaim 1, wherein the door comprises at least one cross-member implantedbetween the lining and the door panel and disposed at the bottom of thehole to avoid the tearing off thereof by the retention pin upon thelateral impact.
 9. Motor vehicle body according to claim 8, wherein thecross-member has an internal profile complementary to that of theretention pin.
 10. Motor vehicle body according to claim 2, wherein thehole is a delimited hole on the door lining.
 11. Motor vehicle bodyaccording to claim 2, wherein the means for retaining the door comprisetwo retention pins and two holes each respectively facing a retentionpin when the door is in the closed position and distributed in thevicinity of the center of entry of the door.
 12. Motor vehicle bodyaccording to claim 3, wherein the means for retaining the door comprisetwo retention pins and two holes each respectively facing a retentionpin when the door is in the closed position and distributed in thevicinity of the center of entry of the door.
 13. Motor vehicle bodyaccording to claim 2, wherein each of the at least one retention pin isfixed to a counter element stamped locally on the side beam.
 14. Motorvehicle body according to claim 3, wherein each of the at least oneretention pin is fixed to a counter element stamped locally on the sidebeam.
 15. Motor vehicle body according to claim 4, wherein each of theat least one retention pin is fixed to a counter element stamped locallyon the side beam.
 16. Motor vehicle body according to claim 2, whereineach of the at least one retention pin is fixed on a continuous grooveprovided over the whole length of the web of the side beam.
 17. Motorvehicle body according to claim 3, wherein each of the at least oneretention pin is fixed on a continuous groove provided over the wholelength of a web of the side beam.
 18. Motor vehicle body according toclaim 4, wherein each of the at least one retention pin is fixed on acontinuous groove provided over the whole length of the a web of theside beam.